This relates generally to wireless communications circuitry, and more particularly, to electronic devices that have wireless communications circuitry with multiple antennas.
Electronic devices such as portable computers and cellular telephones are often provided with wireless communications capabilities. For example, electronic devices may use long-range wireless communications circuitry such as cellular telephone circuitry to communicate using cellular telephone bands at 850 MHz, 900 MHz, 1800 MHz, 1900 MHz, and 2100 MHz. Electronic devices may use short-range wireless communications links to handle communications with nearby equipment. For example, electronic devices may communicate using the WiFi® (IEEE 802.11) bands at 2.4 GHz and 5 GHz and the Bluetooth® band at 2.4 GHz.
Antenna performance affects the ability of a user to take advantage of the wireless capabilities of an electronic device. If antenna performance is not satisfactory, calls may be dropped or data transfer rates may be come undesirably slow. To ensure that antenna performance meets design criteria, it may sometimes be desirable to provide an electronic device with multiple antennas. In the event that one of the antennas in the device is not performing as well as desired, another of the antennas can be switched into use. Schemes in which antennas are switched into use in real time based on antenna performance criteria are sometimes referred to as antenna diversity schemes.
Care must be taken when implementing an antenna diversity scheme in an electronic device. If poor decisions are made in controlling wireless device circuitry or if the wireless circuitry in a device is insufficiently flexible, wireless performance and power consumption performance may suffer.
It would therefore be desirable to be able to provide improved wireless communications circuitry for wireless electronic devices with multiple antennas.